A traffic police personnel wears a mask to protect himself from pollution as smog engulfs Delhi (Photo credit: IANS)

New Delhi, November 7: The air quality in Delhi improved to 'poor' on Wednesday from 'very poor' as stubble burning continued in neighbouring states. According to data from the Central Pollution Control Board (CPCB), the Air Quality Index (AQI) of Delhi was 276, which falls in the 'poor' category. On Tuesday, twenty-five areas in Delhi-NCR recorded ‘very poor’ quality air.

After Diwali celebrations, air pollution in Delhi is expected to rise. The air quality may turn to ‘Severe Plus Emergency’ category on Thursday. Weather analysts say that while currently the polluting north-westerly winds are blowing higher at 5,000 meters, bringing a temporary relif to the region, the particles will start settling down, adding to pollution on Diwali. Delhi Air Pollution: People Stage Protest Outside Environment Ministry Office.

Threat of air quality reverting to 'severe-plus' looms, depending on the weather conditions and how the Delhi-NCR celebrates its Diwali. According to System of Air Quality and Weather Forecasting And Research (SAFAR), PM2.5 levels are expected to spike, bringing the regions's air quality back to 'emergency' for two days -- November 8 and 9 -- if Delhi bursts even 50 per cent of firecrackers that it did on last year's Diwali.

Coarser and highly dangerous PM2.5 or particles with diameter less than 2.5 mm continue to dominate the pollution factor in Delhi, and are still at least four times higher than the national standards and nine times the international standards. (With agency inputs)